This invention relates to articles in which discrete charges of a flavor generating media are burned to release tobacco flavors. More particularly, this invention relates to electrically heated articles.
It is known to provide smoking articles in which a flavor bed of tobacco or tobacco-derived material is heated, without combustion of tobacco, to release tobacco flavors without producing all the normal products of tobacco combustion. For example, it is known to provide a smoking article having a bed of tobacco-derived material and a combustible heat source. A smoker draws air through or around the heat source, heating it, and the heated air passes through the flavor bed, releasing tobacco flavors that are drawn into the smoker's mouth. The heat source temperature is dependent on how the smoker uses the article, so that the flavor release rate varies widely from user to user, and from article to article for a particular user.
Articles that produce the taste and sensation of smoking by heating tobacco electrically are also known. However, in some known electrically heated articles the temperature was not consistent because the output of the electrical power source was not well regulated, so that the release of flavors also was not consistent. In other known electrically heated articles the power source was external to the article and inconvenient.
Commonly-owned, co-pending U.S. patent application Ser. No. 444,746, filed Dec. 1, 1989, teaches heating, but not burning, discrete charges of a flavor generating media to produce an aerosol. Heating discrete charges eliminates sidestream smoke. Heating, but not burning, the flavor generating media eliminates many of the normal products of combustion. However, the control circuitry required to heat flavor generating media without burning it often is complicated.
It would be desirable to be able to provide an electrically heated article which produces a predetermined release of flavor with each puff.
It would also be desirable to be able to provide such an article which consistently for each puff reaches its operating temperature quickly and remains at that temperature long enough to cause burning of its flavor source, while at the same time minimizing the consumption of energy.
It would further be desirable to be able to provide such an article which is self-contained.
It would still further be desirable to be able to provide such an article which can have the appearance of a conventional cigarette, but does not produce sidestream smoke, and is not hot between puffs.